1. Field of the Invention
The present invention relates to apparatus for handling and filtering paint during paint operations and in particular, relates to the cleaning of such paint equipment and apparatus used in the automotive industry.
2. Prior Art
In the art of painting automobiles, paint is conveyed from a large holding tank and passed through a filter canister and paint booth prior to being either manually or mechanically applied to the automobile. The paint is filtered as it passes through the filter canister. The filter canister contains a metal sieve in which a filter bag is placed. The canister top is designed such that the paint flowing into it is directed downwardly into the sieve opening. With this type of arrangement, the flow of the paint through the sieve results in an accumulation of paint sludge along the interior walls of the canister.
The paint sludge is problematic for various reasons. For example, the paint sludge may clot or coagulate, often dislodging from the walls with the consequent risk of clogging the Teflon tubes that convey the paint to the applicator and interfering with the paint flow therethrough. In addition, metal shards within the sludge can be released into the system and puncture the Teflon tubing. Such problems lead to decreased production due to both scheduled and unscheduled maintenance.
Additionally, when a change of colour is mandated during paint operations, a solvent is flushed through the entire system at approximately 1.0-1.7 MPa for several days. The solvent is conveyed through the system in a way similar to the paint. The main flow of the solvent is directed through the vertical height of the sieve. However, the high pressure flow of solvent makes inefficient contact with the accumulated sludge formed on the canister walls. If the sludge is not properly removed in its entirety, contamination of the new colour of paint may result.
Various mechanical methods are also employed to clean the interior walls of the filter canister. The walls are typically scoured with a brush. However, this cleaning method may result in bristles falling off the brush and being subsequently introduced into the paint system. Obviously, bristles inadvertently sprayed onto a vehicle must be removed resulting quality problems and production downtime. Cloth rags are also used as a means to clean the filter canister. However, the use of cloth rags may lead to the introduction of lint deposits into the paint system that also similarly lead to paint defects. Moreover the use of either a brush or a cloth rag requires maintenance personnel to directly expose their hands and arms to the solvent""s harsh chemicals.
U.S. Pat. No. 4,176,797 (Kemp) discloses a fluid mixer and comminuter for paint. The apparatus is used in the mixing of paint stored in conventional paint cans. The apparatus includes an elongated rod having an axis and a pair of discs, at least one of the discs having perforations therethrough adjacent to the rod. Rotation of the rod at high speed causes the paint to enter through the perforations and subsequently be forced radially outwardly from between the discs, thereby promoting mixing of the paint. The apparatus is not used in the removal of debris from paint and does not include a sieve or filter canister, as in the present invention.
The present invention is intended to overcome the disadvantages associated with the prior art cleaning methods mentioned above. As such, an object of the present invention is to provide a simple, inexpensive yet effective device for cleaning the walls of a filter canister.
This object is achieved by providing a fluted stack agitator assembly for placement into the sieve located in the paint canister. The stack agitator includes a cylindrical magnet within its cylindrical body. Conical flutes are circumferentially attached to the exterior of the cylindrical body. The flutes contain apertures or holes which are vertically misaligned with respect to one another such that the apertures are vertically staggered. The magnet which is inserted into the hollow cylinder body is secured in place by a metal screw that is threadingly engaged into the top of the magnet. The screw has an integrally formed handle that permits the manipulation of the assembled device. Thus, when cleaning solvent passes through the system, the flutes re-direct the flow of the solvent to the walls of the canister in the manner hereinafter described to achieve better cleaning thereof.
An additional object of the present invention is to provide an assembly which prevents the accumulation of sludge within the canister during painting operations. When used without the magnet, the stack agitator assembly according to this invention may be installed within the sieve and canister to re-direct the paint flow towards the sides of the canister. This assists in preventing the build-up of sludge along the walls.
Accordingly, there is provided an apparatus for removing debris from painting fluids comprising a cylindrical canister having a fluid inlet and fluid outlet. The canister means has a longitudinal axis substantially parallel to the flow direction of the fluid. A cylindrical filter is concentrically located within the canister for collecting debris from the fluid upon passage of the fluid therethrough. An agitator assembly is concentrically located within the filter and includes a support means having at least a conical flute attached thereto and oriented substantially transversely to the flow direction. The flute has apertures for passage of at least a portion of the fluid therethrough. The flute redirects a portion of the fluid against the filter or canister to thereby remove collected debris. The painting fluids may be either paint or solvents used to clean the apparatus. The support means may include a magnet for collection of metallic debris.
The various features of novelty which characterize the invention are pointed out with more particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated and described a preferred embodiment of the invention.